What potential negative effect does burning zinc in cremation have?

Burning zinc in cremation can emit harmful smoke, which is a significant concern due to the toxic compounds released during the combustion process. Zinc, when exposed to high temperatures, can vaporize and produce zinc oxide and other harmful byproducts. These substances can be dangerous to both the environment and human health, as they may contribute to air pollution and respiratory issues for those in proximity to the cremation process.

While the other options may touch on valid concerns regarding cremation practices or materials, the specific issue with zinc relates directly to the harmful smoke produced, marking it as particularly relevant in discussions about safety and environmental impact in the cremation industry.